1. Field of the Invention
The present invention relates to an image forming apparatus, such as a printer, a copier, a facsimile, a complex machine including functions of these apparatuses, etc., employing an electro-photographic system.
2. Discussion of the Background Art
As an electro-photograph engine employed in an image forming apparatus is demanded to have high resolution and to operate at high speed, a plurality of exposure devices are installed or an exposure device having a plurality of emission points is employed. As a result, a number of electronic devices for exposure is necessarily increased, recently. As an exposure device, a semiconductor laser is generally used.
However, since being significantly weak, the device is difficult to handle. As prior-arts, JPA Nos. 2000-278471 and 8-336055 are exemplified.